Field of the Invention
The invention generally relates to a memory and a method of fabricating the same, and in particular, to a resistive random access memory and a method of fabricating the same.
Description of Related Art
The resistive random access memory (RRAM) is a memory unit which has been widely studied recently because of its advantages of high memory density (e.g., the memory unit occupies a small area), fast operating speed, low power consumption, and low costs. According to the principle of operating the RRAM, when a high voltage is applied to a dielectric material, a conductive path may be formed within the dielectric material, such that the dielectric material is changed from the high-resistance state to the low-resistance state; after that, the dielectric material may return to the high-resistance state if the “reset” step is performed. In this way, the dielectric material may provide two distinct states respectively corresponding “0” and “1”, such that it may serve as a memory unit for storing digital information.
In various RRAMs, the hafnium oxide-based resistive random access memory draws great attention because of excellent durability and fast switching speed. However, the currently used titanium/hafnium oxide (Ti/HfO2) type resistive random access memory is often difficult to stay in the low-resistance state at a high temperature, which may degrade the so-called “high-temperature data retention”. Accordingly, it is necessary to conduct relevant researches for further improvement.